具有推力矢量控制系统的导弹流体动力

Fluid Forces on a Missile with Control System of Vectorial Thrust

采用数值模拟方法研究了带有摆动喷管的导弹水下发射时燃气流场与水流场的相互干扰 ,及其对导弹所受水动力和气动力的影响 .计算采用燃气泡物理模型 ,通过水流场和气流场的耦合计算模拟整个流场的形态 .对水流场采用势流理论 ,通过三维 Hess- Smith方法进行求解 ;对燃气流场 ,以 Euler方程为基本方程 ,采用无波动、无自由参数的耗散差分格式 (NND差分格式 )进行求解 .在燃气泡壁面 ,水流场和燃气流场通过速度条件和压力条件相互耦合 .给出了不同时刻水流场和气流场的物理量分布、喷管摆动角与导弹力矩的关系 ,并对燃气泡的演变过程作了分析 .

The interaction between the flow field of exhausted gas and water field, which occurs after the ignition of an under-water missile, as well as its effect on the hydro-force, thrust and moment acting on the missile, were investigated. It is based on the physical model of exhausted-gas-bubble and numerically simulating the entire flow field by coupling calculation of the water field and gas field. As for the water flow field, three-dimensional Hess-Smith method, which is based on the potential theory and panel technique, is employed to deal with the problem. For the gas flow field, the explicit non oscillatory containing no free parameters and dissipative scheme' (NND scheme) of the finite difference method is utilized in the body-fitted coordinate to solve the governing partial differential equation-the Euler equation. The two fields are coupling with each other by satisfying continuous conditions both in normal velocity and pressure on the gas bubble boundary. A number of physical parameters in both gas and water fields at different time were presented. The relation between the angle of nozzle and the moment of missile, and the detailed growing process of gas bubble were also given.